air conditioner

[Mike S]

This is what works for me. I didn't want to cut into roof or pay that much for a roof mount.

This is the AC on drawer glide on folding shelf.


This shows the AC inserted through an access door opening. Just retract AC and close door and you are ready to go.

Hope this is another idea although I saw others here that have a version of it.

Thanks dpjeansonne. I've seen your previous post and this is going to be my back-up plan. That is, if I can't get adequate ventilation for the compresor with it in the trailer, I'll slide it out when I want to use it.

[aggie79]

Hi all,

I'm a longtime lurker. Rather than start another air conditioner thread, I'll revive an old thread with a similar theme.

I've started a new CT to camper conversion project. One day I'll get around to posting a build thread, but right now I'm not motivated to do that so I apologize. I'm building up a 7x16 Charmac Stealth cargo trailer that I purchased brand new in March. The time has come to install an A/C unit.

I want your input on my install. Here's the plan: I want to mount a household window A/C unit on the side of my trailer. BUT, I don't want the window unit to protrude from the side of the trailer. So I'm planning to keep the unit inside the trailer, except for the hot air vent. The hot air from the condenser coils will be vented to the outside through a hole in the exterior wall. In other words, the vent in the rear of the A/C for the condenser with be flush with the exterior wall of the trailer. The side vents of the A/C (the vents for the mechanical parts) will be kept within the trailer and vent upwards through a small compartment, and through a vent on the roof of the trailer. This is similar to the way I've seen some R/V refrigerators vented. Possibly I'll put a small 12V fan in the compartment to assist with venting. However, when I've tested my window unit, the mechanical parts don't seem to produce a lot of heat.

I haven't seen anyone do it this way, so I want to get some input in advance. Maybe it wont work. What problems to do you foresee with this method?

Thanks for the input.

Mike
Spokane Washington

For most window units the intake air flow for the condensor cooling is on the sides of the unit. The exhaust side of the condensor cooling is through the back of the unit. In addition to ducting the exhaust you will need to duct the supply air for cooling the condensor. If the ducting one or both sides of the condensor air flow significantly reduce air volume, you will experience with freezing of the coils, reduced cooling efficiency, or both. You will also need figure out how to deal with the condensate from the evaporater. On some window units, to gain efficiency, the condensate is "kicked up" to the condensor to improve its efficiency.

After building a teardrop (with an integrated PetCool HVAC unit) I've been lurking around the CTC section for some time. If I decide to build one, then I too want a permanent installation without the AC protruding from the side. I also don't want to deal with the complexity and sealing challenges of "sliding" window unit. My preference is for the AC to be mounted high for better cooling inside and minimize stratification of the cooling.

What I have been considering as an option is to use a "through wall" unit rather than a window unit. A through wall unit has the both the intake and exhaust condensor air flow at the back of the unit and not on the sides of the unit. A cargo door would be installed at the back of the unit and would be opened at the campsite. For the condensate, I would extend a drain line either through the floor of the CT or pipe it in, with a trap, to the grey water tanks.

There are two downsides with a through wall unit compared to a window unit. First, they are more expensive than a window unit. Second, it can be hard to find sizes less than 8,000 Btuh.

[Mike S]

For most window units the intake air flow for the condensor cooling is on the sides of the unit. The exhaust side of the condensor cooling is through the back of the unit. In addition to ducting the exhaust you will need to duct the supply air for cooling the condensor. If the ducting one or both sides of the condensor air flow significantly reduce air volume, you will experie.....

Thanks for the input aggie79. On my unit, the condensate comes out through a hole. I plan to make a drain line out the bottom of the trailer or possibly to the grey water tank. I'll post some pictures when I get my install completed.

[MtnDon]

...... The side vents of the A/C (the vents for the mechanical parts) will be kept within the trailer and vent upwards through a small compartment, and through a vent on the roof of the trailer. This is similar to the way I've seen some R/V refrigerators vented.

RV fridges vent their hot air upwards and through the roof or an upper wall vent.

The side vents on a window unit are intake vents to allow air to enter the section that is meant to hang outside. The air that is exhausted through the condenser fins at the rear enters through the side vents. Channeling that air with a roof vent would mean the hot outside air would be pulled from the roof down against the natural flow pattern, and then through the condenser fins to be blown back outside. I believe that creates too many corners and too many interruptions to smooth air flow. If that air can not move freely the A/C will run longer and not cool as well as it should.

IMO, the most effective method for a thru the sidewall may be to copy one of the installations that has a slide to push the A/C outside when it is needed. There have been a few TD installations where the intake side vent air is channeled from underneath IIRC. Some have worked better than others. A search should find 'em.

[aggie79]

There have been a few TD installations where the intake side vent air is channeled from underneath IIRC. Some have worked better than others. A search should find 'em.

One good-functioning example of this is how Planovet installed the AC window unit in his teardrop: http://www.littleswissteardrop.com/air.html.

For a cargo trailer conversion, instead of ducting to the bottom of the trailer you could duct the intake and exhaust behind the unit through the sidewall. Since the condenser air flow paths are designed to be exposed to the elements, the sidewall openings wouldn't need to be covered except for aesthetic reasons. Other than a slight loss of cargo trailer interior volume and carrying around the weight of the AC unit when it is not needed, I see no downsides to permanently mounting the window unit rather than dealing with the complexity of the slides.

In my sketches for possible CTC layouts, I have the AC unit in a floor to ceiling appliance cabinet with the fridge at the floor (12v/120v unit - no propane), microwave in the middle and AC unit at the top. Of course, if you have multipurpose CTC such as a toy hauler, you probably can't permanently commit that much interior volume for appliances so this design would work except perhaps at the front of the trailer.

Take care,
Tom

[flboy]

This is what works for me. I didn't want to cut into roof or pay that much for a roof mount.

This is the AC on drawer glide on folding shelf.


This shows the AC inserted through an access door opening. Just retract AC and close door and you are ready to go.

Hope this is another idea although I saw others here that have a version of it.

Thanks dpjeansonne. I've seen your previous post and this is going to be my back-up plan. That is, if I can't get adequate ventilation for the compresor with it in the trailer, I'll slide it out when I want to use it.

Nice Install. This is my solution. I used a window unit after finding out the portables just don't do well and I didn't want a large unit up top. This one runs off my little 1600W Generator with juice to spare! I can pull the motorcycle in with no problem and the 4 wheeler will straddle the opening when I put that in. I put the AC in a cabinet up front when traveling. The cover latches down from inside so it literally takes less than a minute to install and turn on.

[Mike S]

...... The side vents of the A/C (the vents for the mechanical parts) will be kept within the trailer and vent upwards through a small compartment, and through a vent on the roof of the trailer. This is similar to the way I've seen some R/V refrigerators vented.

RV fridges vent their hot air upwards and through the roof or an upper wall vent.

The side vents on a window unit are intake vents to allow air to enter the section that is meant to hang outside. The air that is exhausted through the condenser fins at the rear enters through the side vents. Channeling that air with a roof vent would mean the hot outside air would be pulled from the roof down against the natural flow pattern, and then through the condenser fins to be blown back outside. I believe that creates too many corners and too many interruptions to smooth air flow. If that air can not move freely the A/C will run longer and not cool as well as it should.

IMO, the most effective method for a thru the sidewall may be to copy one of the installations that has a slide to push the A/C outside when it is needed. There have been a few TD installations where the intake side vent air is channeled from underneath IIRC. Some have worked better than others. A search should find 'em.

Interesting points. I didn't consider that the side vents sucked the air in to cool the condenser. Inhibiting that flow definitely wouldn't be good. Maybe I can come up with a good intake system. Otherwise, I guess sliding the unit out will be my back up plan.

[Mike S]

flboy I like the flap over the top of the unit. I was consider something like that even if my unit was completely internal. I'd be worried about my 6000 BTU A/C keeping up if it were on the floor. My trailer looks like the same size as yours. Does your A/C keep up?

[Gunguy05]

There have been a few TD installations where the intake side vent air is channeled from underneath IIRC. Some have worked better than others. A search should find 'em.

One good-functioning example of this is how Planovet installed the AC window unit in his teardrop: http://www.littleswissteardrop.com/air.html.

For a cargo trailer conversion, instead of ducting to the bottom of the trailer you could duct the intake and exhaust behind the unit through the sidewall. Since the condenser air flow paths are designed to be exposed to the elements, the sidewall openings wouldn't need to be covered except for aesthetic reasons. Other than a slight loss of cargo trailer interior volume and carrying around the weight of the AC unit when it is not needed, I see no downsides to permanently mounting the window unit rather than dealing with the complexity of the slides.

In my sketches for possible CTC layouts, I have the AC unit in a floor to ceiling appliance cabinet with the fridge at the floor (12v/120v unit - no propane), microwave in the middle and AC unit at the top. Of course, if you have multipurpose CTC such as a toy hauler, you probably can't permanently commit that much interior volume for appliances so this design would work except perhaps at the front of the trailer.

Take care,
Tom

I don't have a drawing of it, but we are going to do something very similar to this. The only difference is that our unit is going to sit on the same level as the galley counter top (a little higher up). So the ducting will be a longer shot down to the road. As a result, we are going to use 2 fans to force air over the back of the condenser.

Good luck, and keep us posted. I always enjoy reading hacks of this concept and see how they pan out in the end.

[flboy]

flboy I like the flap over the top of the unit. I was consider something like that even if my unit was completely internal. I'd be worried about my 6000 BTU A/C keeping up if it were on the floor. My trailer looks like the same size as yours. Does your A/C keep up?

Thanks. I have a 5500 BTU and it absolutely has no problem keeping up. In fact, it cycles off. I was using it for three days two weeks ago in 94 degree weather with about 80% humidity and it worked just fine. I am very pleased with how it works and takes up no space, installs in minutes, and I can still use the ramp for loading and unloading my motorcycles or 4 wheeler.

If you have a 6000 BTU, I'd think it would work great assuming your trailer is insulated. If it is not insulated... I have no idea. This CT's are ovens in the summer with no insulation.

[Mo-Jack]

Check out this new 5,000 BTW air conditioner coming to market in the Spring of 2017. I'm sold.
[ no -- I have no connection or vested interest in this company ]

https://www.indiegogo.com/projects/noria-cool-redefined--3#/

[Shadow Catcher]

I found that the louvered RV vent on the inside directs the cooled air up, however we do have the vent fans (two Antec three speed computer case fans) on and there is enough stand off that even with the vent close it helps recirculate.

[McDave]

https://www.indiegogo.com/projects/nori ... fined--3#/
That's Crazy! I love it. $300.00 is not unreasonable if it works. I'd like to see the insides.

McDave

[Camp Wags]

https://www.indiegogo.com/projects/noria-cool-redefined--3#/
That's Crazy! I love it. $300.00 is not unreasonable if it works. I'd like to see the insides.

McDave

I saw this before, just can't wait a year 4-17.

Anyone using a mini-split unit? The inverter units heat as well as cool.

[lrrowe]

Several posters have recently posted about their mini-split units.